Comment on Inspiring. Innovating.

• markovs_gun@lemmy.world ⁨1⁩ ⁨day⁩ ago

  No. Direct carbon capture is essentially burning fuel in reverse, and at a bare minimum requires roughly the same amount of energy as was released when you burned the fuel. Consider you have a coal power plant operating at 45% energy conversion efficiency. That means for each 1,000 kW of power produced, you actually released 2,200 kW of thermal power total burning the coal. Guess how much energy you need to completely negate the impact of the power plant? It’s much closer to that 2,200 kW number. Let’s say that it only has a thermodynamic requirement of 2000kW due to a favorable storage reaction. However, those machines aren’t 1000% efficient. Even at something like 80% efficiency (much higher than I have ever seen) that still bumps you up to needing 2500 kW, and at 50% efficiency you get to 4000 kW. So in order to run your carbon capture scheme, even in the most optimal conditions, you need more than double (and potentially quadruple) the power output of the plant you’re putting it on. Now you might say “but you could use green energy to run the carbon capture!” But you could also just replace the plant with green energy and bypass the whole problem.

  Carbon capture technology is essentially just PR from fossil fuel companies and it’s a total scam the way that it’s sold to the general public. It’s like if you saw a toddler going around dumping out containers of glitter and said “We need to invest in a better vacuum cleaner to keep the house clean of all this glitter to keep up with this toddler” instead of focusing on stopping the toddler from dumping out more glitter first and worrying about the vacuuming up later. Carbon capture cannot possibly keep up with or make a meaningful dent in total CO2 concentrations until we dramatically reduce emissions. It is a thermodynamic impossibility, and it legitimately pisses me off that there are engineers working on these scams who are either too stupid to realize this or are complacent in the scams.

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  • wetbeardhairs@lemmy.dbzer0.com ⁨1⁩ ⁨day⁩ ago

    You’re 100% correct. The whole point of burning a fuel is to release its energy and oops we have byproducts. Well the second law of thermodynamics explicitly states that if you want to put that CO2 back, you’ve got an energy cost which is *crunches numbers* roughly the same as that released when you burnt it in the first place.

    That being said, if we had some purely green energy sources then it is a laudable goal that could help reduce the harmful effects of climate change.

    Personally I think harvesting CO2 in the ocean is the way to go. It already absorbs tons (gigatons) each year. We just need to figure out a way to coax that dissolved CO2 to fall out of solution as lime without waiting on a geologic timescale for humanity to get murdered by sentient iguanas that love the heat.

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